1. Field
The present invention relates to an electrode paste composition, a front plate of plasma display panel, and a manufacturing method manufactured using the same. Particularly, the present invention relates to the front plate of plasma display panel capable of forming a bus electrode on a substrate directly, and manufacturing method thereof.
2. Background
Plasma display panel (PDP) is a flat panel display device that can display images or information by using a light-emitting phenomenon from plasma discharge. PDP is generally divided into DC-type and AC-type according to panel structure and driving method.
PDP generates plasma discharge in each cell separated by barrier ribs. Thus, PDP is a display device using the light emitting phenomenon of visible rays generated from the energy difference when ultraviolet rays generated by plasma discharge of a gas (such as He, Xe, etc.) provided in each cell returns to the ground state by exciting a phosphor in the cell.
PDP has several advantages such as simple structure, easy manufacturing due to simple structure, high brightness, high luminous efficacy, memory capacity effect, and a wide viewing angle over 160°. Also, PDP can be used for wide screens of 40 or more inches.
FIG. 1 is cross-sectional view illustrating the front plate of PDP in the art.
In FIG. 1, a front plate of PDP 100 is formed a transparent electrode 120, a bus electrode 140, a black matrix 130, a front dielectric layer 150 and a protection layer 160 on a substrate 110 in sequence.
The transparent electrode 120 is made of indium tin oxide (ITO) for transmitting light supplying from a discharging cell.
The bus electrode 140 is made of silver (Ag) having high conductivity.
The bus electrode 140 decreases driving voltage of the transparent electrode 120 of low conductivity because it is made of high conductivity material.
The black matrix 130 is formed between the transparent electrode 120 and the bus electrode 140, and prevents that the bus electrode 140 make fade in other area because it is made of low conductivity material. It will be described following. Also, the black matrix 130 is formed very thin thickness for applying an electric current between the transparent electrode 120 and the bus electrode 140. And, the black matrix 130 plays a role of increasing a contrast of PDP.
The black matrix 130a formed on both sides of the transparent electrode 120 plays a role of dividing between the discharging cells.
The front dielectric layer 150 and the protection layer 160 are laminated on the substrate 110 forming the transparent electrode 120, the bus electrode 140 and the black matrix 130.
The front dielectric layer is accumulated an electric charge generating at the time of plasma discharging.
The protection layer 160 protects damage of the front dielectric layer 150 by sputtering at the time of plasma discharging and increases discharging efficiency of second electrode.
However, as the size of PDP becomes bigger, the length of the transparent electrode 120 becomes longer. Accordingly, the resistance of the transparent electrode 120 becomes high, and due to the above characteristic of the ITO, the electric conductivity becomes low, which becomes a new problem.
To solve this problem, a method of further adding the bus electrode 140 to the transparent electrode 120 was used.
But, such method has a limit.
Thus, as a preferable method presented for solving the problem, the bus electrode 140 was formed directly on the substrate 110.
FIG. 2 is a cross-sectional view illustrating a fading area of the front plate of FIG. 1 when the bus electrode is formed directly on the substrate.
In FIG. 2, in case the bus electrode 140 is formed directly on the substrate 110, the fading area 142 is generated around the substrate 110 contacting with the bus electrode 140.
This fading area is made because a silver ion (Ag+) reacts with a tin (Sn) on the surface of the substrate 110 when silver (Ag), main material of the bus electrode 140, contacts the substrate 110.
In short, in case the bus electrode 140 is formed directly on the substrate 110, there was a problem to cause fading on the substrate 110.
The above references are incorporated herein by reference where appropriate for teachings of additional or alternative details, features and/or technical background.